We frequently get such question on why such-and-such does not have a forum to itself.
Let's me give you this fact for you to consider. Condensed matter physics is the LARGEST sub-division in physics, and in fact, can easily be argued as the largest subtopic in physics. Still, do you see a forum solely dedicated to this subject area? Go take a look around. It shares the subforum with Atomic/molecular physics, and computational physics! Imagine that! Even a subject area that is the LARGEST in the field of physics does not have a forum all to itself!
So already, the argument of importance, of significance, and of size has no bearing on a subject matter getting its own forum. What is more important are (i) frequency of the topic being posted (ii) the level of SUSTAINED interest in that topic (iii) the number of regular members participating in that topic. It is of no point to create a forum for a topic just because ... There has to be an online demand for it in this forum that can justify such a creation.
So forget what you think about the subject matter in general. Do you think your topic qualifies in all the 3 criteria to justify the creation of its own forum? Do you think the posting frequency matches that of, say, the posting frequency in the Relativity forum?